WO2025089903A1 - Method and apparatus for determining repetition factor of uplink control channel signal in non-terrestrial communication system - Google Patents

Abstract

The present disclosure is to configure a method for transmitting an uplink signal in a wireless communication system. A method performed by a base station comprises the steps of: transmitting, to a terminal, a message including information about candidates for a repetition factor indicating a repetition factor of an uplink control channel; receiving, from the terminal, a message including response information for configuring repetitive transmission of the uplink control channel; according to preset criteria for determining the repetition factor of the uplink control channel on the basis of the response information, determining the repetition factor of the uplink control channel; and receiving an uplink control channel signal from the terminal as much as the determined repetition factor of the uplink control channel.

Description

Method and device for determining repetition factor of uplink control channel signal in non-terrestrial communication system

The present disclosure relates to a device and method for setting up repetitive transmission of an uplink control channel signal in a non-terrestrial communication system, and more particularly, to a device and method for determining a repetition factor of an uplink control channel signal.

Communication networks (e.g., 5G communication networks, 6G communication networks, etc.) are being developed to provide improved communication services compared to existing communication networks (e.g., LTE (long term evolution), LTE-A (advanced), etc.). A 5G communication network (e.g., NR (new radio) communication network) can support not only a frequency band below 6 GHz but also a frequency band above 6 GHz. That is, the 5G communication network can support FR1 band and/or FR2 band. A 5G communication network can support various communication services and scenarios compared to an LTE communication network. For example, usage scenarios of a 5G communication network can include eMBB (enhanced Mobile BroadBand), URLLC (Ultra Reliable Low Latency Communication), mMTC (massive Machine Type Communication), etc.

6G communication networks can support various communication services and scenarios compared to 5G communication networks. 6G communication networks can satisfy requirements of ultra-performance, ultra-bandwidth, ultra-space, ultra-precision, ultra-intelligence, and/or ultra-reliability. 6G communication networks can support various and wide frequency bands and can be applied to various usage scenarios (e.g., terrestrial communication, non-terrestrial communication, sidelink communication, etc.).

To improve coverage in non-terrestrial communication environments, various discussions have been conducted in the Rel-18 NTN RAN#1 meeting. In RAN1#110, coverage-related performance results of various physical channels and services in a reference NTN environment were reviewed. As a result, it was concluded that repeated transmission of PUCCH (Physical Uplink Control Channel) for Msg4 HARQ-ACK (Hybrid Automatic Repeat Request Acknowledgement) is necessary to meet the coverage requirements.

In this repetitive transmission setup procedure, information related to a repetition factor indicating the number of times an uplink control channel signal is repetitively transmitted may be signaled. However, since additional signaling is required to set the repetitive transmission procedure of the uplink control channel signal, signaling overhead may occur. Therefore, a setup method for repetitive transmission of an uplink control channel that can reduce signaling overhead is required.

Meanwhile, the technology that serves as the background for the invention was written to promote understanding of the background for the invention, and may include content that is not a prior art already known to a person with ordinary knowledge in the field to which the technology belongs.

The present disclosure may provide a device and method for setting a repetition factor for repeated transmission of an uplink control channel without using additional signaling in a communication system.

The technical objectives to be achieved in the present disclosure are not limited to those mentioned above, and other technical tasks not mentioned can be considered by a person having ordinary skill in the art to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure described below.

As an example of the present disclosure, a method of operating a base station in a wireless communication system may include the steps of transmitting a message including information regarding candidates of a repetition factor indicating a number of times of repeated transmission of an uplink control channel to a terminal, receiving a message including response information for setting repeated transmission of an uplink control channel from the terminal, determining a repetition factor of the uplink control channel based on the response information according to a preset criterion for determining the repetition factor of the uplink control channel, and receiving an uplink control channel signal from the terminal by the number of the determined repetition factors of the uplink control channel.

Here, the response information may be characterized by including information for requesting repeated transmission of the uplink control channel.

Here, the response information may be characterized by including information indicating whether the terminal supports repeated transmission of the uplink control channel, which is information distinct from information for requesting repeated transmission of the uplink control channel.

Here, the repetition factor of the uplink control channel may be characterized in that it is determined based on statistical values of candidates of the repetition factor according to the preset criteria.

Here, the repetition factor of the uplink control channel may be determined based on the number of times the response message is repeatedly transmitted, according to the preset criteria.

Here, the step of signaling information indicating a repetition factor of the uplink control channel to the terminal may be further included.

Here, the step of signaling information indicating a repetition factor of the uplink control channel to the terminal may include the step of determining whether to signal information indicating a repetition factor of the uplink control channel based on candidates of the repetition factor and the response information, the step of mapping at least some of the candidates of the repetition factor to codepoints based on the signaling whether to signal, and the step of signaling information indicating the determined repetition factor of the uplink control channel using the codepoint.

Here, the step of mapping at least some of the candidates of the repetition factor to code points may be characterized by mapping a number of candidates of the repetition factor determined based on the number of bits of an information field indicating the repetition factor of the uplink control channel to code points.

Here, the step of mapping at least some of the candidates of the repetition factor to code points may be characterized by mapping the candidates of the repetition factor to code points based on priorities of the at least some of the candidates of the repetition factor.

As an example of the present disclosure, a method of operating a terminal in a wireless communication system may include the steps of: receiving a message including information regarding candidates of a repetition factor indicating a repetition factor of an uplink control channel from a base station; transmitting a message including response information for setting up repeated transmission of an uplink control channel to the base station; and determining a repetition factor of the uplink control channel based on the response information according to a preset criterion for determining the repetition factor of the uplink control channel; and transmitting an uplink control channel signal from the terminal by the determined repetition factor of the uplink control channel.

Here, the response information may be characterized by including information for requesting repeated transmission of the uplink control channel.

Here, the response information may be characterized by including information indicating whether the terminal supports repeated transmission of the uplink control channel, which is information distinct from information for requesting repeated transmission of the uplink control channel.

Here, the repetition factor of the uplink control channel may be characterized in that it is determined based on statistical values of candidates of the repetition factor according to the preset criteria.

Here, the repetition factor of the uplink control channel may be determined based on the number of times the response message is repeatedly transmitted, according to the preset criteria.

Here, the step of receiving information indicating a repetition factor of the uplink control channel from the base station may be further included.

Here, the method may further include a step of mapping at least some of the candidates of the repetition factor to code points, and the repetition factor of the uplink control channel may be set based on information indicating the repetition factor of the uplink control channel using the code points.

Here, the step of mapping at least some of the candidates of the repetition factor to code points may be characterized by mapping a number of candidates of the repetition factor determined based on the number of bits of an information field indicating the repetition factor of the uplink control channel to code points.

Here, the step of mapping at least some of the candidates of the repetition factor to code points may be characterized by mapping the candidates of the repetition factor to code points based on priorities of the at least some of the candidates of the repetition factor.

As an example of the present disclosure, a base station operating in a wireless communication system includes at least one transmitter, at least one receiver, at least one processor, and at least one memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform a specific operation, wherein the specific operation comprises: transmitting a message including information regarding candidates of a repetition factor indicating a number of times of repeated transmission of an uplink control channel to a terminal, receiving a message including response information for setting repeated transmission of the uplink control channel from the terminal, determining the repetition factor of the uplink control channel based on the response information according to a preset criterion for determining the repetition factor of the uplink control channel, and receiving an uplink control channel signal from the terminal by the determined repetition factor of the uplink control channel.

As an example of the present disclosure, in a wireless communication system, a terminal includes at least one transmitter, at least one receiver, at least one processor, and at least one memory operably connected to the at least one processor and storing instructions that, when executed, cause the at least one processor to perform a specific operation, wherein the specific operation comprises: receiving a message including information regarding candidates of a repetition factor indicating a repetition factor of an uplink control channel from a base station, transmitting a message including response information for setting up repeated transmission of the uplink control channel to the base station, determining the repetition factor of the uplink control channel based on the response information according to a preset criterion for determining the repetition factor of the uplink control channel, and transmitting an uplink control channel signal from the terminal by the determined repetition factor of the uplink control channel.

The above-described aspects of the present disclosure are only some of the preferred embodiments of the present disclosure, and various embodiments reflecting the technical features of the present disclosure can be derived and understood by those skilled in the art based on the detailed description of the present disclosure to be described below.

The following effects may be achieved by embodiments based on the present disclosure.

The present disclosure may provide a device and method for setting a repetition factor for repeated transmission of an uplink control channel without using additional signaling in a communication system.

The effects obtainable from the embodiments of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by a person having ordinary skill in the art to which the technical configuration of the present disclosure is applied, from the description of the embodiments of the present disclosure below. That is, unintended effects resulting from implementing the configuration described in the present disclosure can also be derived by a person having ordinary skill in the art from the embodiments of the present disclosure.

The drawings attached below are intended to aid in understanding the present disclosure and may provide embodiments of the present disclosure together with detailed descriptions. However, the technical features of the present disclosure are not limited to specific drawings, and the features disclosed in each drawing may be combined with each other to form a new embodiment. Reference numerals in each drawing may mean structural elements.

Figure 1a is a conceptual diagram illustrating a first embodiment of a non-terrestrial network.

Figure 1b is a conceptual diagram illustrating a second embodiment of a non-terrestrial network.

Figure 2a is a conceptual diagram illustrating a third embodiment of a non-terrestrial network.

Figure 2b is a conceptual diagram illustrating a fourth embodiment of a non-terrestrial network.

Figure 2c is a conceptual diagram illustrating a fifth embodiment of a non-terrestrial network.

FIG. 3 is a block diagram illustrating a first embodiment of a communication node constituting a non-terrestrial network.

FIG. 4 is a block diagram illustrating a first embodiment of communication nodes performing communication.

FIG. 5a is a block diagram illustrating a first embodiment of a transmission path.

FIG. 5b is a block diagram illustrating a first embodiment of a receiving path.

FIG. 6a is a conceptual diagram illustrating a first embodiment of a protocol stack of a user plane in a non-terrestrial network based on transparent payload.

FIG. 6b is a conceptual diagram illustrating a first embodiment of a protocol stack of a control plane in a non-terrestrial network based on transparent payload.

FIG. 7a is a conceptual diagram illustrating a first embodiment of a protocol stack of a user plane in a non-terrestrial network based on regenerative payload.

FIG. 7b is a conceptual diagram illustrating a first embodiment of a protocol stack of a control plane in a non-terrestrial network based on regenerative payload.

Figure 8 is a conceptual diagram illustrating an embodiment of a 4-Step RACH (random access channel) procedure.

FIG. 9 is a conceptual diagram illustrating one embodiment of a non-repeatedly transmitted uplink control channel and a repetitively transmitted uplink control channel.

FIG. 10 is a diagram illustrating an embodiment of a repetitive transmission procedure of an uplink control channel for coverage improvement in an NTN environment.

FIG. 11 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

FIG. 12 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

FIG. 13 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

FIG. 14 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

FIG. 15 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

FIG. 16 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

FIG. 17 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

FIG. 18 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

FIG. 19 is a diagram illustrating a method for determining and signaling a repetition factor according to the present disclosure.

FIG. 20 is a diagram illustrating a method for checking initial conditions for determining a repetition factor according to the present disclosure.

FIG. 21 is a diagram illustrating an operation for determining and signaling a repetition factor according to the present disclosure.

FIG. 22 is a diagram illustrating an operation for determining and signaling a repetition factor according to the present disclosure.

FIG. 23 is a diagram illustrating an operation for determining and signaling a repetition factor according to the present disclosure.

FIG. 24 is a diagram illustrating an operation for determining and signaling a repetition factor according to the present disclosure.

FIG. 25 illustrates an example of a procedure for setting a repetition factor of an uplink control channel signal according to one embodiment of the present disclosure.

The present disclosure may have various modifications and various embodiments, and thus specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the present disclosure to specific embodiments, but should be understood to include all modifications, equivalents, and alternatives included in the spirit and technical scope of the present disclosure.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are only used to distinguish one component from another. For example, without departing from the scope of the present disclosure, the first component could be referred to as the second component, and similarly, the second component could also be referred to as the first component. The term "and/or" can mean a combination of a plurality of related listed items or any one of a plurality of related listed items.

In the present disclosure, "at least one of A and B" can mean "at least one of A or B" or "at least one of combinations of one or more of A and B." Additionally, in the present disclosure, "at least one of A and B" can mean "at least one of A or B" or "at least one of combinations of one or more of A and B."

In the present disclosure, (re)transmitting can mean “transmitting”, “retransmitting”, or “transmitting and retransmitting”, (re)setting can mean “setting”, “resetting”, or “setting and resetting”, (re)connecting can mean “connecting”, “reconnecting”, or “connecting and reconnecting”, and (re)connecting can mean “connecting”, “reconnecting”, or “connecting and reconnecting”.

When it is said that a component is "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components in between. On the other hand, when it is said that a component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

The terminology used in this disclosure is only used to describe specific embodiments and is not intended to be limiting of the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, it should be understood that the terms "comprises" or "has" and the like are intended to specify that a feature, number, step, operation, component, part or combination thereof described in the specification is present, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense unless expressly defined in this disclosure.

Hereinafter, with reference to the attached drawings, preferred embodiments of the present disclosure will be described in more detail. In order to facilitate an overall understanding in describing the present disclosure, the same reference numerals are used for the same components in the drawings, and redundant descriptions of the same components are omitted. In addition to the embodiments explicitly described in the present disclosure, operations according to combinations of embodiments, extensions of embodiments, and/or modifications of embodiments can be performed. The performance of some operations can be omitted, and the order of performing the operations can be changed.

In an embodiment, even if a method (e.g., transmitting or receiving a signal) performed by a first communication node among communication nodes is described, a second communication node corresponding thereto can perform a method (e.g., receiving or transmitting a signal) corresponding to the method performed by the first communication node. That is, if an operation of a UE (user equipment) is described, a base station corresponding thereto can perform an operation corresponding to the operation of the UE. Conversely, if an operation of a base station is described, a UE corresponding thereto can perform an operation corresponding to the operation of the base station.

The base station may be referred to as a NodeB, an evolved NodeB, a gNodeB (next generation node B), a gNB, a device, an apparatus, a node, a communication node, a BTS (base transceiver station), an RRH (radio remote head), a TRP (transmission reception point), a RU (radio unit), an RSU (road side unit), a radio transceiver, an access point, an access node, etc. The UE may be referred to as a terminal, a device, an apparatus, a node, a communication node, an end node, an access terminal, a mobile terminal, a station, a subscriber station, a mobile station, a portable subscriber station, an OBU (on-broad unit), etc.

In the present disclosure, signaling may be at least one of upper layer signaling, MAC signaling, or PHY (physical) signaling. A message used for upper layer signaling may be referred to as an "upper layer message" or an "upper layer signaling message". A message used for MAC signaling may be referred to as a "MAC message" or a "MAC signaling message". A message used for PHY signaling may be referred to as a "PHY message" or a "PHY signaling message". Upper layer signaling may refer to a transmission and reception operation of system information (e.g., a master information block (MIB), a system information block (SIB)) and/or an RRC message. MAC signaling may refer to a transmission and reception operation of a MAC control element (CE). PHY signaling may refer to a transmission and reception operation of control information (e.g., downlink control information (DCI), uplink control information (UCI), sidelink control information (SCI)).

In the present disclosure, "an operation (e.g., a transmission operation) is set" may mean that "setting information for the operation (e.g., an information element, a parameter)" and/or "information instructing performance of the operation" are signaled. "An information element (e.g., a parameter) is set" may mean that the information element is signaled. In the present disclosure, "a signal and/or a channel" may mean a signal, a channel, or "a signal and a channel," and a signal may be used to mean "a signal and/or a channel."

The communication network to which the embodiment is applied is not limited to what is described below, and the embodiment can be applied to various communication networks (e.g., a 4G communication network, a 5G communication network, and/or a 6G communication network). Here, the communication network can be used in the same meaning as the communication system.

Figure 1a is a conceptual diagram illustrating a first embodiment of a non-terrestrial network.

Referring to FIG. 1A, the non-terrestrial network may include a satellite (110), a communication node (120), a gateway (130), a data network (140), etc. A unit including the satellite (110) and the gateway (130) may be a remote radio unit (RRU). The non-terrestrial network illustrated in FIG. 1A may be a transparent payload-based non-terrestrial network. The satellite (110) may be a low earth orbit (LEO) satellite, a medium earth orbit (MEO) satellite, a geostationary earth orbit (GEO) satellite, a high elliptical orbit (HEO) satellite, or an unmanned aircraft system (UAS) platform. The UAS platform may include a high altitude platform station (HAPS). The non-GEO satellite may be a LEO satellite and/or a MEO satellite.

The communication node (120) may include a communication node located on the ground (e.g., UE, terminal) and a communication node located off the ground (e.g., airplane, drone). A service link may be established between the satellite (110) and the communication node (120), and the service link may be a radio link. The satellite (110) may be referred to as an NTN payload. The gateway (130) may support a plurality of NTN payloads. The satellite (110) may provide a communication service to the communication node (120) using one or more beams. The shape of the reception range (footprint) of the beam of the satellite (110) may be elliptical or circular.

In non-terrestrial networks, three types of service links can be supported as follows:

- Earth-fixed: the service link may be provided by beam(s) that continuously cover the same geographic area at all times (e.g. Geosynchronous Orbit (GSO) satellites).

- Quasi-earth-fixed: the service link may be provided by beam(s) that cover one geographic area for a limited period and another geographic area for another period (e.g., NGSO (non-GSO) satellites producing steerable beams).

- Earth-moving: Service links may be provided by beam(s) moving over the surface of the Earth (e.g., NGSO satellites producing fixed beams or non-steerable beams).

The communication node (120) can perform communication (e.g., downlink communication, uplink communication) with the satellite (110) using 4G communication technology, 5G communication technology, and/or 6G communication technology. Communication between the satellite (110) and the communication node (120) can be performed using an NR-Uu interface and/or a 6G-Uu interface. When DC (dual connectivity) is supported, the communication node (120) can be connected to not only the satellite (110) but also other base stations (e.g., base stations supporting 4G functions, 5G functions, and/or 6G functions), and can perform DC operations based on technologies defined in the 4G standard, the 5G standard, and/or the 6G standard.

The gateway (130) may be located on the ground, and a feeder link may be established between the satellite (110) and the gateway (130). The feeder link may be a wireless link. The gateway (130) may be referred to as a “non-terrestrial network (NTN) gateway.” Communication between the satellite (110) and the gateway (130) may be performed based on an NR-Uu interface, a 6G-Uu interface, or a satellite radio interface (SRI). The gateway (130) may be connected to a data network (140). A “core network” may exist between the gateway (130) and the data network (140). In this case, the gateway (130) may be connected to the core network, and the core network may be connected to the data network (140). The core network may support 4G communication technology, 5G communication technology, and/or 6G communication technology. For example, the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc. Communication between the gateway (130) and the core network may be performed based on a NG-C/U interface or a 6G-C/U interface.

As in the embodiment of Fig. 1b below, in a non-terrestrial network based on transparent payload, a base station and a core network may exist between a gateway (130) and a data network (140).

Figure 1b is a conceptual diagram illustrating a second embodiment of a non-terrestrial network.

Referring to FIG. 1b, a gateway may be connected to a base station, the base station may be connected to a core network, and the core network may be connected to a data network. Each of the base station and the core network may support 4G communication technology, 5G communication technology, and/or 6G communication technology. Communication between the gateway and the base station may be performed based on an NR-Uu interface or a 6G-Uu interface, and communication between the base station and the core network (e.g., AMF, UPF, SMF) may be performed based on an NG-C/U interface or a 6G-C/U interface.

Figure 2a is a conceptual diagram illustrating a third embodiment of a non-terrestrial network.

Referring to FIG. 2a, the non-terrestrial network may include satellite #1 (211), satellite #2 (212), communication node (220), gateway (230), data network (1240), etc. The non-terrestrial network illustrated in FIG. 2a may be a regenerative payload-based non-terrestrial network. For example, each of satellite #1 (211) and satellite #2 (212) may perform a regenerative operation (e.g., a demodulation operation, a decoding operation, a re-encoding operation, a re-modulation operation, and/or a filtering operation) on a payload received from another entity constituting the non-terrestrial network (e.g., a communication node (220), a gateway (230)) and transmit the regenerated payload.

Each of satellite #1 (211) and satellite #2 (212) may be a LEO satellite, a MEO satellite, a GEO satellite, a HEO satellite, or a UAS platform. The UAS platform may include HAPS. Satellite #1 (211) may be connected to satellite #2 (212), and an inter-satellite link (ISL) may be established between satellite #1 (211) and satellite #2 (212). The ISL may operate in a radio frequency (RF) frequency or an optical band. The ISL may be optionally established. The communication node (220) may include a ground-located communication node (e.g., UE, terminal) and a non-ground-located communication node (e.g., an airplane, a drone). A service link (e.g., a wireless link) may be established between satellite #1 (211) and the communication node (220). Satellite #1 (211) may be referred to as an NTN payload. Satellite #1 (211) may provide communication services to a communication node (220) using one or more beams.

The communication node (220) can perform communication (e.g., downlink communication, uplink communication) with satellite #1 (211) using 4G communication technology, 5G communication technology, and/or 6G communication technology. Communication between satellite #1 (211) and the communication node (220) can be performed using an NR-Uu interface or a 6G-Uu interface. When DC is supported, the communication node (220) can be connected to other base stations (e.g., base stations supporting 4G functions, 5G functions, and/or 6G functions) as well as satellite #1 (211), and can perform DC operations based on technologies defined in the 4G standard, the 5G standard, and/or the 6G standard.

The gateway (230) may be located on the ground, and a feeder link may be established between satellite #1 (211) and the gateway (230), and a feeder link may be established between satellite #2 (212) and the gateway (230). The feeder link may be a wireless link. If an ISL is not established between satellite #1 (211) and satellite #2 (212), the feeder link between satellite #1 (211) and the gateway (230) may be established mandatory. Communication between each of satellite #1 (211) and satellite #2 (212) and the gateway (230) may be performed based on an NR-Uu interface, a 6G-Uu interface, or SRI. The gateway (230) may be connected to a data network (240).

As in the embodiments of FIGS. 2b and 2c below, a “core network” may exist between the gateway (230) and the data network (240).

FIG. 2b is a conceptual diagram illustrating a fourth embodiment of a non-terrestrial network, and FIG. 2c is a conceptual diagram illustrating a fifth embodiment of a non-terrestrial network.

Referring to FIGS. 2b and 2c, the gateway may be connected to a core network, and the core network may be connected to a data network. The core network may support 4G communication technology, 5G communication technology, and/or 6G communication technology. For example, the core network may include AMF, UPF, SMF, etc. Communication between the gateway and the core network may be performed based on a NG-C/U interface or a 6G-C/U interface. The function of the base station may be performed by a satellite. That is, the base station may be located on a satellite. The payload may be processed by a base station located on a satellite. Base stations located on different satellites may be connected to the same core network. One satellite may have one or more base stations. In the non-terrestrial network of FIG. 2b, an ISL between satellites may not be established, and in the non-terrestrial network of FIG. 2c, an ISL between satellites may be established.

Meanwhile, entities (e.g., satellites, base stations, UEs, communication nodes, gateways, etc.) constituting the non-terrestrial network illustrated in FIG. 1a, FIG. 1b, FIG. 2a, FIG. 2b, and/or FIG. 2c may be configured as follows. In the present disclosure, entities may be referred to as communication nodes.

FIG. 3 is a block diagram illustrating a first embodiment of a communication node constituting a non-terrestrial network.

Referring to FIG. 3, a communication node (300) may include at least one processor (310), a memory (320), and a transceiver device (330) that is connected to a network and performs communication. In addition, the communication node (300) may further include an input interface device (340), an output interface device (350), a storage device (360), etc. Each component included in the communication node (300) may be connected by a bus (370) and communicate with each other.

However, each component included in the communication node (300) may be connected through an individual interface or individual bus centered around the processor (310), rather than a common bus (370). For example, the processor (310) may be connected to at least one of a memory (320), a transceiver (330), an input interface device (340), an output interface device (350), or a storage device (360) through a dedicated interface.

The processor (310) can execute program commands stored in at least one of the memory (320) and the storage device (360). The processor (310) may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to the embodiments are performed. Each of the memory (320) and the storage device (360) may be configured with at least one of a volatile storage medium or a nonvolatile storage medium. For example, the memory (320) may be configured with at least one of a read only memory (ROM) or a random access memory (RAM).

Meanwhile, communication nodes performing communication in a communication network (e.g., a non-terrestrial network) may be configured as follows. The communication node illustrated in Fig. 4 may be a specific embodiment of the communication node illustrated in Fig. 3.

FIG. 4 is a block diagram illustrating a first embodiment of communication nodes performing communication.

Referring to FIG. 4, each of the first communication node (400a) and the second communication node (400b) may be a base station or a UE. The first communication node (400a) may transmit a signal to the second communication node (400b). The transmission processor (411) included in the first communication node (400a) may receive data (e.g., a data unit) from a data source (410). The transmission processor (411) may receive control information from the controller (416). The control information may include at least one of system information, RRC configuration information (e.g., information configured by RRC signaling), MAC control information (e.g., MAC CE), or PHY control information (e.g., DCI, SCI).

The transmitting processor (411) can perform a processing operation (e.g., an encoding operation, a symbol mapping operation, etc.) on data to generate data symbol(s). The transmitting processor (411) can perform a processing operation (e.g., an encoding operation, a symbol mapping operation, etc.) on control information to generate control symbol(s). In addition, the transmitting processor (411) can generate synchronization/reference symbol(s) for a synchronization signal and/or a reference signal.

The Tx MIMO processor (412) can perform spatial processing operations (e.g., a precoding operation) on data symbol(s), control symbol(s), and/or synchronization/reference symbol(s). An output (e.g., a symbol stream) of the Tx MIMO processor (412) can be provided to modulators (MODs) included in the transceivers (413a to 413t). The modulators (MODs) can perform processing operations on the symbol streams to generate modulation symbols and perform additional processing operations (e.g., an analog conversion operation, an amplification operation, a filtering operation, an upconversion operation) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (413a to 413t) can be transmitted via the antennas (414a to 414t).

The signals transmitted by the first communication node (400a) may be received by the antennas (464a to 464r) of the second communication node (400b). The signals received by the antennas (464a to 464r) may be provided to the demodulators (DEMODs) included in the transceivers (463a to 463r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a down-conversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (462) may perform a MIMO detection operation on the symbols. The receiving processor (461) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (461) may be provided to a data sink (460) and a controller (466). For example, data may be provided to the data sink (460) and control information may be provided to the controller (466).

Meanwhile, the second communication node (400b) can transmit a signal to the first communication node (400a). The transmitting processor (468) included in the second communication node (400b) can receive data (e.g., data units) from a data source (467) and perform a processing operation on the data to generate data symbol(s). The transmitting processor (468) can receive control information from the controller (466) and perform a processing operation on the control information to generate control symbol(s). In addition, the transmitting processor (468) can perform a processing operation on a reference signal to generate reference symbol(s).

The Tx MIMO processor (469) can perform spatial processing operations (e.g., precoding operations) on data symbol(s), control symbol(s), and/or reference symbol(s). An output (e.g., a symbol stream) of the Tx MIMO processor (469) can be provided to modulators (MODs) included in the transceivers (463a to 463t). The modulators (MODs) can perform processing operations on the symbol streams to generate modulation symbols and can perform additional processing operations (e.g., an analog conversion operation, an amplification operation, a filtering operation, an upconversion operation) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (463a to 463t) can be transmitted via the antennas (464a to 464t).

The signals transmitted by the second communication node (400b) may be received by the antennas (414a to 414r) of the first communication node (400a). The signals received by the antennas (414a to 414r) may be provided to the demodulators (DEMODs) included in the transceivers (413a to 413r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a down-conversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (420) may perform a MIMO detection operation on the symbols. The receiving processor (419) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (419) may be provided to a data sink (418) and a controller (416). For example, data may be provided to the data sink (418) and control information may be provided to the controller (416).

Memories (415 and 465) can store data, control information, and/or program code. Scheduler (417) can perform scheduling operations for communications. The processors (411, 412, 419, 461, 468, 469) and controllers (416, 466) illustrated in FIG. 4 may be the processor (310) illustrated in FIG. 3 and may be used to perform the methods described in the present disclosure.

FIG. 5a is a block diagram illustrating a first embodiment of a transmission path, and FIG. 5b is a block diagram illustrating a first embodiment of a reception path.

Referring to FIGS. 5A and 5B, a transmission path (510) may be implemented in a communication node that transmits a signal, and a reception path (520) may be implemented in a communication node that receives a signal. The transmission path (510) may include a channel coding and modulation block (511), an S-to-P (serial-to-parallel) block (512), an N IFFT (Inverse Fast Fourier Transform) block (513), a P-to-S (parallel-to-serial) block (514), a CP (cyclic prefix) addition block (515), and an UC (up-converter) (UC) (516). The receiving path (520) may include a DC (down-converter) (521), a CP removal block (522), an S-to-P block (523), an N FFT block (524), a P-to-S block (525), and a channel decoding and demodulation block (526). Here, N may be a natural number.

In the transmission path (510), information bits may be input to a channel coding and modulation block (511). The channel coding and modulation block (511) may perform a coding operation (e.g., a low-density parity check (LDPC) coding operation, a polar coding operation, etc.) and a modulation operation (e.g., a quadrature phase shift keying (QPSK), a quadrature amplitude modulation (QAM), etc.) on the information bits. An output of the channel coding and modulation block (511) may be a sequence of modulation symbols.

The S-to-P block (512) can convert modulation symbols in the frequency domain into parallel symbol streams to generate N parallel symbol streams. N can be an IFFT size or an FFT size. The N IFFT block (513) can perform an IFFT operation on the N parallel symbol streams to generate signals in the time domain. The P-to-S block (514) can convert the output (e.g., parallel signals) of the N IFFT block (513) into a serial signal to generate a serial signal.

The CP addition block (515) can insert a CP into a signal. The UC (516) can up-convert the frequency of the output of the CP addition block (515) to an RF (radio frequency) frequency. Additionally, the output of the CP addition block (515) can be filtered at baseband before up-conversion.

A signal transmitted from the transmit path (510) may be input to the receive path (520). An operation in the receive path (520) may be an inverse operation of the operation in the transmit path (510). The DC (521) may down-convert the frequency of the received signal to a frequency of a baseband. The CP removal block (522) may remove a CP from the signal. An output of the CP removal block (522) may be a serial signal. The S-to-P block (523) may convert the serial signal into parallel signals. The NFFT block (524) may perform an FFT algorithm to generate N parallel signals. The P-to-S block (525) may convert the parallel signals into a sequence of modulation symbols. The channel decoding and demodulation block (526) may perform a demodulation operation on the modulation symbols and perform a decoding operation on the result of the demodulation operation to restore data.

In FIGS. 5A and 5B, Discrete Fourier Transform (DFT) and Inverse DFT (IDFT) can be used instead of FFT and IFFT. Each of the blocks (e.g., components) in FIGS. 5A and 5B can be implemented by at least one of hardware, software, or firmware. For example, some of the blocks in FIGS. 5A and 5B can be implemented by software, and the remaining blocks can be implemented by hardware or a “combination of hardware and software.” In FIGS. 5A and 5B, one block can be subdivided into multiple blocks, multiple blocks can be integrated into one block, some blocks can be omitted, and blocks supporting other functions can be added.

Meanwhile, NTN reference scenarios can be defined as shown in [Table 1] below.

In the non-terrestrial network illustrated in FIG. 1a and/or FIG. 1b, if the satellite (110) is a GEO satellite (e.g., a GEO satellite supporting the transparent function), this may be referred to as “Scenario A.” In the non-terrestrial network illustrated in FIG. 2a, FIG. 2b, and/or FIG. 2c, if each of satellite #1 (211) and satellite #2 (212) is a GEO satellite (e.g., a GEO supporting the regeneration function), this may be referred to as “Scenario B.”

If the satellite (110) in the non-terrestrial network illustrated in FIG. 1a and/or FIG. 1b is a LEO satellite having steerable beams, this may be referred to as “Scenario C1”. If the satellite (110) in the non-terrestrial network illustrated in FIG. 1a and/or FIG. 1b is a LEO satellite having beams move with satellite, this may be referred to as “Scenario C2”. If each of satellite #1 (211) and satellite #2 (212) in the non-terrestrial network illustrated in FIG. 2a, FIG. 2b, and/or FIG. 2c is a LEO satellite having steerable beams, this may be referred to as “Scenario D1”. In the non-terrestrial network illustrated in FIG. 2a, FIG. 2b, and/or FIG. 2c, where each of satellite #1 (211) and satellite #2 (212) are LEO satellites having beams that travel together with the satellites, this may be referred to as “Scenario D2.”

Parameters for NTN reference scenarios defined in [Table 1] can be defined as shown in [Table 2] below.

Additionally, in the NTN reference scenario defined in [Table 1], the delay constraint can be defined as in [Table 3] below.

FIG. 6a is a conceptual diagram illustrating a first embodiment of a protocol stack of a user plane in a non-terrestrial network based on transparent payload, and FIG. 6b is a conceptual diagram illustrating a first embodiment of a protocol stack of a control plane in a non-terrestrial network based on transparent payload.

Referring to FIGS. 6A and 6B, user data may be transmitted and received between a UE and a core network (e.g., UPF), and control data (e.g., control information) may be transmitted and received between the UE and a core network (e.g., AMF). Each of the user data and the control data may be transmitted and received via a satellite and/or a gateway. The protocol stack of the user plane illustrated in FIG. 6A may be applied identically or similarly to a 6G communication network. The protocol stack of the control plane illustrated in FIG. 6B may be applied identically or similarly to a 6G communication network.

FIG. 7a is a conceptual diagram illustrating a first embodiment of a protocol stack of a user plane in a non-terrestrial network based on regenerative payload, and FIG. 7b is a conceptual diagram illustrating a first embodiment of a protocol stack of a control plane in a non-terrestrial network based on regenerative payload.

Referring to FIGS. 7A and 7B, user data and control data (e.g., control information) may be transmitted and received through an interface between a UE and a satellite (e.g., a base station), respectively. The user data may mean a user PDU (protocol data unit). A protocol stack of a satellite radio interface (SRI) may be used to transmit and receive user data and/or control data between a satellite and a gateway. The user data may be transmitted and received through a GTP (GPRS (general packet radio service) tunneling protocol)-U tunnel between the satellite and a core network.

Meanwhile, in a non-terrestrial network, a base station can transmit system information (e.g., SIB19) including satellite assistance information for NTN access. A UE can receive system information (e.g., SIB19) from a base station, check satellite assistance information included in the system information, and perform communication (e.g., non-terrestrial communication) based on the satellite assistance information. SIB19 can include information element(s) defined in [Table 4] below.

NTN-Config defined in [Table 4] may include information element(s) defined in [Table 5] below.

EphemerisInfo defined in [Table 5] may include information element(s) defined in [Table 6] below.

Coverage Enhancement in a Non-Terrestrial Network (NTN) environment has been selected as a Rel-18 Work Item and has been discussed extensively in the Rel-18 NTN RAN#1 meeting. In RAN1#110, coverage-related performance results of various physical channels and services in a reference NTN environment were reviewed. As a result, it was concluded that the Physical Uplink Control Channel (PUCCH) for Msg4 HARQ-ACK (Hybrid Automatic Repeat Request Acknowledgement) needs to be enhanced to satisfy the coverage requirement. The PUCCH transmission operation for Msg4 HARQ-ACK can be set and performed according to the procedure described below.

Figure 8 is a conceptual diagram illustrating an embodiment of a 4-Step RACH (random access channel) procedure.

Referring to FIG. 8, Msg4 HARQ-ACK may be a signal transmitted by a terminal to a base station to notify that an uplink 4-Step RACH (Random Access Procedure) has been successfully performed. The situation illustrated in FIG. 8 may be a situation in which a normal RRC connection establishment procedure has not been completed. In order to transmit Msg4 HARQ-ACK of FIG. 8, a common PUCCH resource may be used instead of a dedicated PUCCH resource dedicated to each terminal.

Although only the performance verification for Msg4 HARQ-ACK in 4-Step RACH was performed in the Rel-18 RAN1 meeting. However, the common PUCCH resource used to transmit Msg4 HARQ-ACK can be continuously used until the dedicated PUCCH resource is allocated to the terminal. Therefore, a method to improve the coverage for the subsequent common PUCCH resource-based transmission was also agreed upon. As a specific technique for improving the coverage, it was agreed to apply repetitive transmission. The repetitive transmission technique for improving the coverage can be as described below.

FIG. 9 is a conceptual diagram illustrating one embodiment of a non-repeatedly transmitted uplink control channel and a repetitively transmitted uplink control channel.

Referring to Fig. 9, when transmitting 4 PUCCH symbols per slot, examples of normal transmission (repeated transmission not applied) and examples of repeated transmission twice are illustrated. When repeated transmission is performed as in Fig. 2, the same symbols are repeatedly transmitted temporally using additional slots.

The procedures for setting up repeat transmissions to improve NTN coverage as agreed upon at the Rel-18 meeting may be as described below.

FIG. 10 is a diagram illustrating an embodiment of a repetitive transmission procedure of an uplink control channel for coverage improvement in an NTN environment.

Referring to Fig. 10, first, in the SIB (System Information Block), 1) the RSRP (Reference Signal Received Power) threshold, which is the criterion for repeated transmission, and 2) the repetition factor candidates that can be supported by each base station can be set. Here, the repetition factors that can be supported for NR NTN in Rel-18 are agreed to be {1,2,4,8}.

If repetition factor candidates are set in SIB, each terminal can transmit a repetition request message through Msg3 depending on whether it supports repetition transmission (capability), whether an RSRP threshold is set in SIB, and the comparison result between the measured RSRP and the RSRP threshold.

And, the base station that receives the information related to the repetition request from the terminal can determine the number of repetitions to be performed by each terminal and transmit the repetition factor information regarding the number of repetitions through the DAI (Downlink Assignment Index) field of the DCI (Downlink Control Information). Here, the transmitted repetition factor can be selected from the repetition factor candidates transmitted in the SIB. The terminal can perform repeated transmission from the Msg4-HARQ ACK depending on whether it supports it or not based on the DAI field of the DCI.

On the other hand, if the repetition factor candidates are not set in the SIB, the legacy operation up to Rel-17 is performed, and the operation related to the repeated transmission of the uplink control channel signal may not be performed. In this case, the repetition request may be conveyed as 2 state information. Here, the first state (State 1) may indicate a repetition request, and the 0th state (State 0) may indicate a repetition no request (No indication). The repetition request and the support availability report (Capability Report) may not be distinguished in signaling.

That is, the procedure for setting up repeated transmission of uplink control channels to improve coverage in an NTN environment can be as shown in the table below.

According to the RAN1 meeting for Rel-18, the information about repetition factor of uplink control channel can be transmitted through DCI format 1_0 with CRC (cyclic redundancy check) scrambled by TC-RNTI of Msg4. Here, the information about repetition factor can be allocated to the 2-bit DAI field that was reserved in that situation. Currently, a total of 4 supportable repetition factors (1, 2, 4, 8) can be set for Rel-18 NR NTN coverage enhancement.

According to RAN1#114b, the way of assigning bits and code points to each repetition factor may be as described below. Always using 2 bits, ‘00’, ‘01’, ‘10’, and ‘11’ may be assigned to the repetition factors set as the first/second/third/fourth, respectively. However, if the number of supportable repetition counts of SIB is 2 or less, specific code points (e.g., ‘10’ or ‘11’) may not be used.

Accordingly, according to the present disclosure, a method and procedure for determining the number of repetitions between a base station and a terminal for coverage improvement in an NTN environment can be provided. In order to explain the proposed techniques, the following mathematical notations are first defined.

R _total : A set of repetition factors that can be assigned for PUCCH transmission based on Msg4 HARQ-ACK and common PUCCH resources defined in the standard. R _total = {1, 2, 4, 8} based on Rel-18.

R _SIB (⊂ R _total ): Represents a set of candidates for the number of repetitions set by the base station through SIB.

|R _SIB |: The size of the R _SIB set, which represents the number of repetition number candidates that are actually being transmitted through SIB.

r _i : The number of repetitions set to the i-th element of SIB, which is the i(1≤i≤|R _SIB |)th element of R _SIB . That is, R _SIB = {r ₁ , ... , r _|RSIB| }.

S ₁ : Indicates the first state (repeat request or repeat transmission support) in the two-state information for transmitting a repeat request.

S ₀ : In the 2-state information for transmitting a repeat request, indicates the 0th state (repeat request not supported and/or repeat transmission not supported).

According to one embodiment of the present disclosure, a method for determining the number of repetitions without using signaling for a repetition factor is proposed. The method for determining the number of repetitions without using signaling for a repetition factor may be as described below.

FIG. 11 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

According to FIG. 11, in step S1101, the base station can receive repetition request information and determine whether the repetition request information transmitted by the terminal is in the S ₁ state. However, the base station may not separately determine information on whether the terminal supports repetition transmission. In this case, there may be a situation where separate capability information (Capability Information) that is distinct from the 2-state repetition request information is not signaled. That is, as agreed in Rel-18, the capability information and the repetition request information may not be distinguished in signaling. In this case, even if the base station receives repetition request information in the S ₀ state from the terminal, it cannot distinguish whether the terminal does not support repetition transmission or supports repetition transmission but does not request repetition of the terminal.

If the status of the repetition request information is S ₀ , i.e., if a repetition request is not indicated, the measured RSRP value may be higher than the RSRP threshold, or the terminal may not support uplink control channel repetition transmission. Considering this, in step S1102, the base station may determine R=1 as the repetition factor of the terminal so as not to perform uplink control channel repetition transmission. However, the base station may not separately transmit the repetition factor information of the terminal to the terminal through signaling such as DCI.

If a terminal supporting uplink control channel repetition transmission transmits the status value of repetition request information of S ₀ (No Indication), the terminal can set the repetition factor to R = 1 and transmit an uplink control channel signal without being specifically notified of the number of repetitions through signaling prior to proceeding with Msg4 HARQ-ACK and common PUCCH resource PUCCH transmission.

On the other hand, for a terminal that does not support uplink channel repeat transmission, the uplink control channel signal can be transmitted in a form that is practically the same as setting the repetition factor to R=1, since repeat transmission is not performed.

In contrast, when the state of the repetition request information is S ₁ , i.e., indicating a repetition request, the RSRP measurement value of the terminal supporting uplink control channel repetition transmission may be lower than the RSRP threshold, or the RSRP threshold may not be set in the SIB. As a result, the channel quality between the base station and the terminal supporting uplink control channel repetition transmission may be poor. Therefore, in step S1103, the base station may configure the terminal to perform uplink control channel repetition transmission.

Base stations and terminals that have set up repeat transmission can set repetition factors according to preset rules.

In one embodiment, the repetition factor may be set to the maximum repetition factor value set in the SIB. In this case, in step S1104, the base station may set the repetition number to R = max(R _SIB ) for maximum coverage enhancement.

Alternatively, the communication environment of the uplink control channel transmission can be assumed to be a channel environment similar to that of the Msg3 PUSCH transmission. In this case, in step S1105, the base station can determine the repetition count as shown in the mathematical formula below by finding the element of R _SIB (excluding 1) closest to the Msg3 PUSCH repetition count R _Msg3 .

Here, the nearest element of R _SIB can be calculated from the values obtained by taking the log of each r _i . That is, the value corresponding to the nearest element of R _SIB can be searched as in the mathematical formula below. This is because the number of iterations is usually determined as an exponent of 2.

Here, if there are two or more r _i having the same argmin value, R can be set to the largest value among them to improve coverage. Or, if there are two or more r _i having the same argmin value, R can be set to the largest value among them to prevent resource waste. Here, 1 can be excluded.

According to another embodiment, in order to set a repetition factor, a criterion may be applied to select a minimum value among values not less than R _Msg3 or a maximum value among values not greater than R _Msg3 , depending on a system environment. Here, both the base station and the uplink control channel repeated transmission supporting terminal know both R _SIB and states S ₁ and R _Msg3 of repetition request information. Therefore, if the terminal knows how to determine the repetition factor, the terminal that actually attempts PUCCH repeated transmission such as Msg4 HARQ-ACK can set the repetition factor equal to the repetition number R determined by the base station and proceed with repeated transmission, without being specifically notified of the repetition number through signaling.

FIG. 12 is a diagram illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

As illustrated in FIG. 12, in step S1201, the base station can receive repetition request information and determine whether the repetition request information transmitted by the terminal is in the S ₁ state. Here, the base station can separately determine information on whether the terminal supports uplink control channel repetition transmission. For example, performance information can be signaled separately from the existing 2-State repetition request information. That is, when the base station receives repetition request information of the S ₀ state from the terminal, the base station can distinguish between a terminal that does not support repetition transmission and a terminal that supports repetition transmission but does not request repetition transmission.

If the status of the repetition request information is S ₀ , i.e., if it does not indicate uplink control channel repetition transmission, the RSRP measurement value of the terminal is higher than the RSRP threshold or the terminal does not support uplink control channel repetition transmission. In step S1202, the base station can check whether the terminal supports uplink control channel repetition transmission.

If the terminal supports uplink control channel repetition transmission, in step S1203, the base station can determine R = min(R _SIB ), i.e., the minimum value among the repetition factors set by the base station, as the repetition factor of the terminal. However, the base station may not separately transmit the determined repetition factor information to the terminal through signaling such as DCI. Meanwhile, the terminal supporting uplink control channel repetition transmission knows the status of R _SIB and its own repetition request information. Therefore, the terminal can set the repetition factor to be equal to the repetition factor R = min(R _SIB ) set by the base station and perform repeated transmission of the uplink control channel signal even without receiving repetition factor information through signaling such as Msg4 HARQ-ACK.

On the other hand, if it is impossible to confirm whether the terminal supports repeated transmission of the uplink control channel or the terminal does not support repeated transmission of the uplink control channel, in step S1204, the base station may confirm whether the terminal does not support repeated transmission of the uplink control channel and may not perform repeated transmission. That is, the base station may determine R=1 as a repetition factor of the corresponding terminal. However, the base station does not separately transmit the determined repetition factor information to the terminal through signaling such as DCI. Meanwhile, the terminal may have transmitted information indicating that it does not support repeated transmission of the uplink control channel or may not support the repeated transmission function of the uplink control channel. Accordingly, the terminal may not perform repeated transmission of the uplink control channel substantially the same as when R=1 even if it does not receive repetition factor information through signaling before performing Msg4 HARQ-ACK and common PUCCH resource-based transmission.

Meanwhile, when the state of the repetition request information is S ₁ , the base station and the terminal can take the same actions as when the state of the repetition request information is S ₁ in FIG. 11 and the related description.

또는

)중의 하나로 미리 결정될 수 있다. 다른 실시예에 따르면, Msg3 PUSCH가 반복 전송된 경우, 상향링크 제어 채널의 반복 인자는 Msg3 PUSCH 반복 인자 기반 기준을 사용하여 결정될 수 있다. 반면, Msg3 PUSCH가 반복 전송되지 않은 경우, 상향링크 제어 채널의 반복 인자는 최대 커버리지 향상 기준을 사용하여 결정될 수 있다. 반복 인자 설정에 관한 기준 및 설정 방식이 정해진 경우, 기지국 및 단말은 기준에 관한 정보를 별도로 시그널링하지 아니하고도 해당 기준의 사용을 인지할 수 있다. 기본적으로 본 개시에 따른 방법의 목적은 시그널링 오버헤드를 절감하고자 하는 바, 가급적 표준 규격을 통해 기준을 사전에 결정하는 것이 바람직하다.Here, the criterion for setting the repetition factor must be determined in advance. If the criterion used is not determined in advance, information about the criterion used needs to be transmitted through separate signaling. For example, the criterion for setting the repetition factor may be the maximum coverage enhancement criterion (R = max(R _SIB )) described above or the Msg3 PUSCH repetition factor-based criterion (e.g.,

or

) can be determined in advance as one of the following. According to another embodiment, if Msg3 PUSCH is repeatedly transmitted, the repetition factor of the uplink control channel can be determined using a Msg3 PUSCH repetition factor-based criterion. On the other hand, if Msg3 PUSCH is not repeatedly transmitted, the repetition factor of the uplink control channel can be determined using a maximum coverage enhancement criterion. If the criterion and the setting method for setting the repetition factor are determined, the base station and the terminal can recognize the use of the criterion without separately signaling information about the criterion. Basically, the purpose of the method according to the present disclosure is to reduce signaling overhead, and therefore, it is desirable to determine the criterion in advance through a standard specification, if possible.

Meanwhile, in order to transmit repetition factor information more dynamically, when dynamically selecting the repetition factor setting criteria, the base station can inform the terminal of the information about the used setting criteria through signaling. Or, the terminal can request the base station for information about the used setting criteria. However, preferably, the repetition factor setting criteria can be determined by the base station or the network.

When the base station informs all terminals in the cell of terminal-specific information about the reference, the base station can transmit the information about the reference through SIB1, SIB19, etc. When the base station informs terminals of terminal-specific information about the reference, the base station can transmit the information about the reference through the DAI field of DCI format 1_0 with CRC scrambled by TC-RNTI of Msg4, which is not used in Proposal 1.

On the other hand, when the terminal requests the base station for information about the criteria, the terminal can request the criteria through a separate PRACH occasion in Msg1, a separate PRACH preamble in case of shared PRACH occasions, or Msg3. When the terminal requests the base station for information about the criteria, the base station can determine the criteria by considering the request of the terminal through Msg4, etc. instead of accepting it as is, and transmit information about the determined criteria.

According to one embodiment of the present disclosure, a 2-bit Msg4 DCI DAI field defined in Rel-18 can be reserved to reduce signaling overhead. Accordingly, if up to 2-bit signaling via Msg4 DCI is required for other functions in the future, the DAI field can be utilized. Alternatively, the embodiment of the present disclosure can be utilized even when future supportable repetition transmission factor candidates, i.e., elements of R _total , are added compared to {1, 2, 4, 8} of Rel-18 and transmission cannot be made using only the DAI field.

FIGS. 13 to 18 are diagrams illustrating a method for determining the number of repetitions without using signaling for a repetition factor according to the present disclosure.

Referring to Figure 13, candidates for repeated arguments can be set in SIB.

According to Case 1 of Fig. 13, the repeated argument candidates in SIB can be set to {1, 2, 4, 8}.

At step S1311, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1312, the terminal determines that it does not support repeated transmission of the uplink control channel and may transmit Msg3 including repetition request information of the S ₀ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel to 1 without separate signaling. Accordingly, the base station and the terminal can avoid performing a repetition transmission operation of the uplink control channel.

According to Case 2 of Fig. 13, the repeated argument candidates in SIB can be set to {1, 2, 4}.

At step S1311, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1312, the terminal determines that it does not support repeated transmission of the uplink control channel and may transmit Msg3 including repetition request information of the S ₀ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel to 1 without separate signaling. Accordingly, the base station and the terminal can avoid performing a repetition transmission operation of the uplink control channel.

Referring to FIG. 14, repetition factor candidates can be set in the SIB. Here, the repetition factor of the uplink control channel can be set to the largest value among the repetition factor candidates set in the SIB to improve coverage.

According to Case 1 of Fig. 14, the repeated argument candidates in SIB can be set to {1, 2, 4, 8}.

At step S1411, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1412, the terminal determines that it supports repeated transmission of the uplink control channel and can transmit Msg3 including repetition request information of the S ₁ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 8, which is the maximum value among the repetition factors set in the SIB. Accordingly, the base station and the terminal can perform a repeated transmission operation of the uplink control channel using the set repetition factor.

According to Case 2 of Fig. 14, the repeated argument candidates in SIB can be set to {1, 2, 4}.

At step S1411, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1412, the terminal determines that it supports repeated transmission of the uplink control channel and can transmit Msg3 including repetition request information of the S ₁ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 4, which is the maximum value among the repetition factors set in the SIB. Accordingly, the base station and the terminal can perform a repeated transmission operation of the uplink control channel using the set repetition factor.

Referring to FIG. 15, repetition factor candidates can be set in SIB. Here, the repetition factor of the uplink control channel can be set based on the repetition factor of the Msg3 PUSCH transmission.

According to Case 1 of Figure 15, the repeated argument candidates in SIB can be set to {1, 2, 8}.

At step S1511, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1512, the terminal determines that it supports repeated transmission of the uplink control channel, and may transmit Msg3 including repetition request information of the S ₁ state to the base station. Here, Msg3 may be repeatedly transmitted four times. That is, the repetition factor of Msg3 PUSCH transmission may be 4.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 2, which is a value that is linearly closest to the repetition factor of the Msg3 PUSCH transmission among the repetition factors set in the SIB. Accordingly, the base station and the terminal can perform a repetition transmission operation of the uplink control channel using the set repetition factor.

According to Case 2 of Fig. 15, the repeated argument candidates in SIB can be set to {2, 32}.

At step S1521, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1522, the terminal determines that it supports repeated transmission of the uplink control channel and can transmit Msg3 including repetition request information of the S ₁ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 32, which has the log value closest to the repetition factor of the Msg3 PUSCH transmission among the repetition factors set in the SIB. Accordingly, the base station and the terminal can perform the repetition transmission operation of the uplink control channel using the set repetition factor.

According to Case 3 of Fig. 15, the candidates for repeated arguments in SIB can be set to {2, 4, 16, 32}.

At step S1531, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1532, the terminal determines that it supports repeated transmission of the uplink control channel and can transmit Msg3 including repetition request information of the S ₁ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 8, which is the minimum value among the repetition factors set in the SIB that are greater than the repetition factor of the Msg3 PUSCH transmission. Accordingly, the base station and the terminal can perform the repetition transmission operation of the uplink control channel using the set repetition factor.

Referring to Figure 16, candidates for repeated arguments can be set in SIB.

According to Case 1 of Fig. 16, the repeated argument candidates in SIB can be set to {1, 2, 4, 8}.

At step S1611, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1612, the terminal determines that it supports repeated transmission of the uplink control channel but does not request repeated transmission of the uplink control channel, and may transmit Msg3 including repetition request information of the S ₀ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel to 1 without separate signaling. Accordingly, the base station and the terminal can avoid performing a repetition transmission operation of the uplink control channel.

According to Case 2 of Fig. 16, the candidates for repeated arguments in SIB can be set to {2, 4, 8}.

At step S1621, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1622, the terminal determines that it does not support repeated transmission of the uplink control channel and may transmit Msg3 including repetition request information of the S ₀ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel to 1 without separate signaling. Accordingly, the base station and the terminal can avoid performing a repetition transmission operation of the uplink control channel.

According to Case 3 of Fig. 16, the repeated argument candidates in SIB can be set to {4, 8}.

At step S1631, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1632, the terminal determines that it does not request repeated transmission of the uplink control channel, and may transmit Msg3 including repetition request information of the S ₀ state to the base station. However, the base station may not be able to confirm whether the terminal supports repeated transmission of the uplink control channel.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel to 1 without separate signaling. Accordingly, the base station and the terminal can avoid performing a repetition transmission operation of the uplink control channel.

Referring to FIG. 17, repetition factor candidates can be set in the SIB. Here, the repetition factor of the uplink control channel can be set to the largest value among the repetition factor candidates set in the SIB to improve coverage.

According to Case 1 of Fig. 17, the candidates for repeated arguments in SIB can be set to {2, 4, 8}.

At step S1711, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1712, the terminal determines that it supports repeated transmission of the uplink control channel and can transmit Msg3 including repetition request information of the S ₁ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 8, which is the maximum value among the repetition factors set in the SIB. Accordingly, the base station and the terminal can perform a repeated transmission operation of the uplink control channel using the set repetition factor.

According to Case 2 of Fig. 17, the repeated argument candidates in SIB can be set to {1, 4}.

At step S1721, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1722, the terminal determines that it supports repeated transmission of the uplink control channel and can transmit Msg3 including repetition request information of the S ₁ state to the base station.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 4, which is the maximum value among the repetition factors set in the SIB. Accordingly, the base station and the terminal can perform a repeated transmission operation of the uplink control channel using the set repetition factor.

Referring to FIG. 18, repetition factor candidates can be set in SIB. Here, the repetition factor of the uplink control channel can be set based on the repetition factor of the Msg3 PUSCH transmission.

According to Case 1 of Fig. 18, the repeated argument candidates in SIB can be set to {2, 4, 8}.

At step S1511, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1512, the terminal determines that it supports repeated transmission of the uplink control channel, and may transmit Msg3 including repetition request information of the S ₁ state to the base station. Here, Msg3 may be repeatedly transmitted four times. That is, the repetition factor of Msg3 PUSCH transmission may be 4.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 4, which is a value that is linearly closest to the repetition factor of the Msg3 PUSCH transmission among the repetition factors set in the SIB. Accordingly, the base station and the terminal can perform a repetition transmission operation of the uplink control channel using the set repetition factor.

According to Case 2 of Fig. 18, the repeated argument candidates in SIB can be set to {2, 16}.

At step S1821, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1822, the terminal determines that it supports repeated transmission of the uplink control channel, and may transmit Msg3 including repetition request information of the S ₁ state to the base station. Here, Msg3 may be repeatedly transmitted four times. That is, the repetition factor of Msg3 PUSCH transmission may be 4.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 2, which has the log value closest to the repetition factor of the Msg3 PUSCH transmission among the repetition factors set in the SIB. Accordingly, the base station and the terminal can perform the repetition transmission operation of the uplink control channel using the set repetition factor.

According to Case 3 of Fig. 18, the repeated argument candidates in SIB can be set to {2, 8, 16}.

At step S1831, the base station may transmit SIB configuration information to the terminal. The SIB configuration information may include information about repetition factor candidates.

At step S1832, the terminal determines that it supports repeated transmission of the uplink control channel, and may transmit Msg3 including repetition request information of the S ₁ state to the base station. Here, Msg3 may be repeatedly transmitted four times. That is, the repetition factor of Msg3 PUSCH transmission may be 4.

As a result, the base station and the terminal can set the repetition factor of the uplink control channel without separate signaling. Here, the repetition factor can be set to 8, which is the minimum value among the repetition factors set in the SIB that are greater than the repetition factor of the Msg3 PUSCH transmission. Accordingly, the base station and the terminal can perform the repetition transmission operation of the uplink control channel using the set repetition factor.

According to another embodiment of the present disclosure, the base station may determine specific repetition numbers among the total possible repetition numbers as candidates for the available repetition numbers by considering the status of the repetition request information of the terminal, and perform bit allocation and signaling for transmitting information about the candidates for the available repetition numbers. The method and procedure for determining the repetition number according to this may be as described below.

FIG. 19 is a diagram illustrating a method for determining and signaling a repetition factor according to the present disclosure.

Referring to Figure 19, the method for determining the number of repetitions can be composed of a total of four steps.

At step S1910, the base station can check the initial conditions to determine the repetition factor of the uplink control channel transmission without performing subsequent steps.

At step S1920, the base station can select candidates for repetition factors to be included in the signaling process.

At step S1930, the base station can select a codepoint allocation priority for the selected repetition factor candidates.

At step S1940, the base station can assign selected repetition factor candidates to code points according to priorities.

Here, step S1910 may be a mandatory step. And, if the judgment result of step S1910 indicates that further steps are necessary, step S1940 may also be a mandatory step. And, steps S1920 and S1930 are optional steps and may be omitted in some cases.

Before the explanation, the related mathematical notations are defined as follows. R ^* _SIB is a subset of R _SIB (R ^* _SIB ⊂ R _SIB ), and can be a set whose elements are the repetition counts selected to be transmitted to each terminal through signaling, considering the status of the repetition request, etc. The size of the R ^* _SIB set (i.e., the number of elements) can be K. In addition, B can indicate the number of bits of a message field for signaling repetition factor information. A total of 2 ^B pieces of information can be expressed in the field. Therefore, the number of selected candidates K (= |R ^* _SIB |) must be less than or equal to 2 ^B.

Each step of the method for determining the number of repetitions according to one embodiment of the present disclosure may be as described below.

FIG. 20 is a diagram illustrating a method for checking initial conditions for determining a repetition factor according to the present disclosure.

Referring to FIG. 20, depending on whether the information indicating whether the terminal's Msg4 HARQ-ACK and common PUCCH resource repeated transmission support is reported to the base station in a separate form from the repetition request information or can be confirmed, the step of checking the initial condition for determining the repetition factor can be divided into two cases. Here, the base station and the terminal can check the status of the required repetition request information, R _SIB or the status of the repetition request information, R _SIB , and whether repeated transmission is supported. Meanwhile, a terminal that does not support repeated transmission of an uplink control channel may not be able to identify the repetition request related information. Therefore, the terminal can basically transmit the uplink control channel non-repeatedly. In this case, the base station performs non-repeated transmission (eg, R=1). Therefore, the repetition request related information can be determined without any problem.

First, according to Case 1 of Fig. 20, the base station may not separately determine whether the terminal supports repeated transmission. In this case, separate performance information that is distinct from the 2-State repetition request information may not be signaled. That is, as agreed upon in Rel-18, the information on whether repeated transmission is supported is not distinct from the repetition request information in terms of signaling. Accordingly, the base station that receives the repetition request information of the S ₀ state from the terminal cannot distinguish whether the terminal does not support repeated transmission or whether the terminal supports repeated transmission but does not request repeated transmission.

First, in step S2011, the base station can determine whether the state of the repetition request information is S ₀ or S _1. If S ₁ , the base station can perform the operations of the subsequent steps of FIG. 19 according to step S2014. If the state of the repetition request information is S ₀ , in step S2012, the base station can determine whether 1 is included in R _SIB set in SIB. That is, the base station can determine whether the terminal actually supports non-repetitive transmission. If 1∈R _SIB , the base station can perform the operations of the subsequent steps of FIG. 19 according to step S2014. This means that when the state of the repetition request information is S ₀ , a terminal supporting repetitive transmission can set the repetition factor to R = 1 and transmit an uplink control channel. A terminal that does not support repetitive transmission does not support repetitive transmission, and therefore can transmit an uplink control channel in the same way as setting the repetition factor to R = 1. Therefore, in both cases, the base station can determine the repetition factor as R=1 to prevent unnecessary waste of PUCCH resources.

R_SIB 인 경우, 기지국은 반복 인자를 1로 설정할 수 없다. 이 경우, 기지국은 반복 인자를 1보다 큰 값으로 설정하게 되어, PUCCH 자원을 낭비할 수 있다. 따라서, S2013 단계에서, 기지국은 상향링크 제어 채널의 반복 전송 동작을 중단할 수 있다. 실질적으로 기지국 및 단말은 모두 R=1로 설정되는 경우와 동일하게 상향링크 제어 채널을 전송할 수 있다. On the other hand, if 1

In case of R _SIB , the base station cannot set the repetition factor to 1. In this case, the base station sets the repetition factor to a value greater than 1, which may waste PUCCH resources. Therefore, in step S2013, the base station can stop the repeated transmission operation of the uplink control channel. In fact, both the base station and the terminal can transmit the uplink control channel in the same way as when R=1 is set.

On the other hand, according to Case 2 of Fig. 20, the base station can separately determine whether the terminal supports repeated transmission. In this case, the information on whether the terminal supports repeated transmission can be signaled separately from the existing 2-State repetition request signaling. That is, the base station that receives S ₀ from the terminal can distinguish whether the terminal is a terminal that does not support repeated transmission or a terminal that supports repeated transmission but does not request repeated transmission.

R_SIB인 경우, S2023 단계에서, 기지국은 단말의 반복 전송 지원 여부를 추가적으로 판단할 수 있다. 만약 단말이 반복 전송을 지원하는 경우, 반복 요청 정보의 상태와 관계없이 단말은 R>1의 반복 인자에 따른 상향링크 제어 채널의 반복 전송을 지원할 수 있다. 따라서, S2025 단계에 따라, 기지국은 도 19의 이후 단계의 동작을 수행할 수 있다. 반면 단말이 반복 전송을 지원하지 아니하거나, 기지국이 단말의 반복 전송 지원 여부를 알 수 없는 경우, (예를 들어, 단말이 반복 전송 지원 여부 관련 시그널링을 지원하지 않는 레거시 단말인 경우), 반복 인자를 1보다 큰 값으로 설정하는 기지국은 PUCCH 자원을 낭비할 수 있다. 따라서, S2024 단계에서, 기지국은 반복 전송 절차의 동작을 중단할 수 있다. In step S2021, the base station can determine whether the status of the repetition request information is S ₀ or S _1. If the repetition request information is S ₁ , the base station can perform the operations of the subsequent steps of FIG. 19 according to step S2025. If the status of the repetition request information is S ₀ , in step S2022, the base station can determine whether 1 is included in R _SIB set in SIB, i.e., whether practical non-repetitive transmission is supported. If 1∈R _SIB , the base station can perform the operations of the subsequent steps of FIG. 19. On the other hand, 1

If R _SIB , in step S2023, the base station can additionally determine whether the terminal supports repeated transmission. If the terminal supports repeated transmission, the terminal can support repeated transmission of the uplink control channel according to a repetition factor of R>1 regardless of the state of the repetition request information. Therefore, in step S2025, the base station can perform the operations of the subsequent steps of FIG. 19. On the other hand, if the terminal does not support repeated transmission or the base station cannot know whether the terminal supports repeated transmission (for example, if the terminal is a legacy terminal that does not support signaling related to whether or not the terminal supports repeated transmission), the base station setting the repetition factor to a value greater than 1 may waste PUCCH resources. Therefore, in step S2024, the base station can stop the operation of the repeated transmission procedure.

A terminal that does not support repetitive transmission is substantially the same as a terminal that does not support repetitive transmission and thus sets the repetition factor to R=1. Therefore, a base station and a terminal that does not support repetitive transmission can perform PUCCH transmission in the same way as when the repetition factor is set to R=1.

Referring back to FIG. 19, at step S1920, the base station can determine R ^* SIB _{, which are repetition factors that can be transmitted through actual signaling, among repetition factors included in R SIB ,} according to the status of repetition request information and R _{Msg3 (the number of Msg3} PUSCH repetitions). Both the base station and the terminal may know the status of the repetition request information and R _SIB and R _Msg3 . Therefore, if the selection conditions for determining repetition factors to be transmitted through actual signaling are determined in advance, the base station and the terminal can perform each process separately to obtain the same result.

According to one embodiment of the present disclosure, the base station and the terminal can determine R ^* _SIB by utilizing the status of the repetition request information.

If the status of the repetition request information indicates S ₀ , i.e., not requesting repeated transmission, the terminal is a terminal that does not support repeated transmission or does not request repeated transmission. In this case, both the base station and the terminal can set K repetition factors from the smallest value among the elements belonging to R _SIB to elements of R ^* _SIB .

On the other hand, if the repetition request state is S ₁ , i.e., indicates a request for repeated transmission, the terminal supports repeated transmission and is a terminal that has transmitted information requesting repeated transmission. In this case, both the base station and the terminal can set K repetition factors, starting from the largest value among the elements belonging to R _SIB , as elements of R ^* _SIB .

According to another embodiment of the present disclosure, the base station and the terminal can determine R ^* _SIB by utilizing the status of the repetition request information and the number of Msg3 PUSCH repetitions.

If the state of the repetition request information indicates S ₀ , i.e., not requesting repeated transmission, the terminal does not support repeated transmission or is a terminal that has not requested repeated transmission. In this case, both the base station and the terminal can set K repetition factors from the smallest value among the elements belonging to R _SIB to elements of R ^* _SIB . That is, if the state of the repetition request information is S ₀ , R ^* _SIB can be determined regardless of R _Msg3 .

On the other hand, if the status of the repetition request information is S ₁ , i.e., indicates requesting repeated transmission, the terminal supports repeated transmission and may be a terminal that has transmitted information requesting repeated transmission. In this case, both the base station and the terminal may set K repetition factors close to R _Msg3 among the elements belonging to R _SIB as elements of R ^* _SIB in the order of proximity from R _Msg3 . Here, the criterion for calculating the proximity repetition factors may be a criterion based on the difference in values when log2 is taken for each repetition factor. That is, K r _i (∈R _SIB ) with the smallest |log ₂ R _Msg3 - log ₂ r _i | for 1≤i≤|R _SIB | may be set as elements of R ^* _SIB in the order of proximity. However, when r _i = 1, it can always have the lowest priority compared to all other values. If the same |log ₂ R _Msg3 - log ₂ r _i | When there are two repetition factors with a larger repetition factor, the element of R ^* _SIB can be determined preferentially.

According to one embodiment of the present disclosure, if there are different repetition factor candidates having the same difference value, a larger repetition factor can be preferentially determined as an element of R ^* _SIB . This may be a way to maximize coverage enhancement. According to another embodiment of the present disclosure, in order to minimize transmission resource waste, if the same difference occurs, a smaller repetition factor (except 1) can be preferentially determined as an element of R ^* _SIB . If there are repetition factors having such the same difference, the criterion for determining the element of R ^* _SIB should be predetermined through the standard. In addition, the criterion for determining the element of R ^* _SIB may be |R _Msg3 - instead of the difference of the repetition factor based on log2. r _i | for 1≤i≤|R _SIB |, that is, it can be based on the linear difference values of the repetition factors.

The method of determining the elements of R ^* _SIB based on the repetition factor candidates can be applied in a signaling or predetermined manner, using the number of Msg3 PUSCH repetition transmissions when Msg3 PUSCH repetition transmissions were supported, or using the status of repetition request information when Msg3 PUSCH repetition transmissions were not supported.

R ^* _SIB can be set as shown in the table below.

As expressed in the table, if K = |R _SIB |, then R ^* _SIB = R _SIB . In this case, step S1920 can be omitted.

Referring back to FIG. 19, the base station and terminal that have determined R ^* _SIB can determine the allocation priority of each element (repetition factor) belonging to R ^* _SIB . Here, the allocation priority may mean the priority in the code point allocation process. In order to determine the allocation priority, the criteria for setting R ^* _SIB , R ^* _SIB , R _SIB , R _Msg3 , repetition request information, etc. may be used. The above information may be information that the base station and terminal know in advance. Therefore, if the criteria for determining the allocation priority are the same between the base station and the terminal, the base station and the terminal can derive the same result value.

The assignment priority of repeating arguments can be set according to the following criteria.

According to one embodiment of the present disclosure, the priorities of the elements of R ^* _SIB can be determined according to the priorities to which each element was assigned in R _SIB .

According to one embodiment of the present disclosure, the priorities of the elements of R ^* _SIB can be determined in the order in which they are first assigned to R ^* _SIB .

According to one embodiment of the present disclosure, the priorities of the elements of R ^* _SIB can be determined such that elements with a smaller value among the elements of R ^* _SIB have a higher allocation priority.

According to one embodiment of the present disclosure, the priorities of the elements of R ^* _SIB can be determined such that elements with a larger value among the elements of R ^* _SIB have a higher allocation priority.

According to one embodiment of the present disclosure, when the state of the repetition request information is S ₀ , the priorities of the elements of R ^* _SIB may be determined such that an element with a smaller value among the elements of R ^* _SIB may have a higher assignment priority. On the other hand, when the state of the repetition request information is S ₁ , the priorities of the elements of R ^* _SIB may be determined such that an element with a larger value (repetition factor) among the elements of R ^* _SIB may have a higher assignment priority.

If code points are not assigned according to priority, the step of determining the assignment priority may be omitted.

Referring back to FIG. 19, the base station and the terminal can allocate bits to each element of R ^* _SIB . If the criteria used in the bit allocation process are agreed upon in advance between the terminal and the base station, the base station and the terminal can use the same bit allocation rule since they know each other's priorities of R ^* _SIB and each element. Here, the allocated bits can be allocated in the order of LSB → MSB (Most Significant Bit) of the field to be used in the signaling process or in the order of MSB → LSB.

The way bits are assigned to each element of R ^* _SIB can be as described below.

According to one embodiment of the present disclosure, a method of allocating bits to each element of R ^* _SIB may be a fixed mapping method in which B bits are always used, and allocation is made by increasing by 1 from a code point of an all-zero bit sequence. For example, when B = 3, repetition factors represented by each B-bit sequence may be allocated in the order of 000, 001, 010, 011, ... If K < 2 ^B and not all code points are assigned to repetition factors, the unassigned code points are not used. In this case, the allocation order may use priority/reverse priority/small repetition count/large repetition count criteria, etc.

According to one embodiment of the present disclosure, a method of allocating bits to each element of R ^* _SIB may be a reservation-based mapping method that determines how many bits of the B bits of the field to use depending on K. When 1 ≤ K ≤ 2 ¹ , 1 bit is used, when 3 ≤ K ≤ 2 ² , 2 bits are used, and when 5 ≤ K ≤ ^{2 3} , 3 bits are used. Thus, when 2 ^{B * - 1} + 1 ≤ K ≤ 2 ^{B *} , among the B bits of the field used for signaling, B ^* (≤ B) bits are used, and the unused (B B ^* ) bits are reserved and can be used for other purposes when necessary. The B ^* bits are allocated by increasing by 1 from the All-zero bit sequence. If K < 2 ^{B *} and not all B ^* bit code points are assigned to repetition factors, the unassigned code points are not used. In this case, the allocation order can use priority/reverse priority/small repetition count/large repetition count criteria, etc.

According to one embodiment of the present disclosure, a method of allocating bits to each element of R ^* _SIB may be an adaptive reservation based mapping method that determines which bits of the B bits of a field to use according to the priority of the repetition factor. For example, assuming a case where B = 2, a case can be considered where the repetition count of the 1st rank is assigned to 0, a repetition factor of the 2nd rank to 10, and a repetition factor of the 3rd rank to 11. These values can be used by inverting the priority assignment bits, such as 1, 00, and 01. In addition, assuming a case where B = 3, a case can be considered where the repetition count of the 1st rank is assigned to 0, a repetition factor of the 2nd rank to 100, a repetition factor of the 3rd rank to 101, a repetition factor of the 4th rank to 111, and a repetition factor of the 5th rank to 111. That is, the repetition factor assigned with the highest probability and having the highest priority is expressed with only one bit corresponding to the MSB or LSB among the B bits in the field, and the remaining B-1 bits are reserved so that they cannot be assigned to the repetition factor. The repetition factors with other priorities have bits that are inverted compared to the repetition factor with the first priority, and are allocated according to the priority with the remaining (B-1) bits. Therefore, when the repetition factor with the highest priority is set, additional savings in signaling overhead are possible. In addition, the adaptive allocation method can express up to 2 ^B-1 +1 cases in the field of B bits. Therefore, when the adaptive allocation method is applied, K ≤ 2 ^B-1 +1 must be satisfied. If K < 2 ^B-1 +1 and there are code points that are not assigned to the repetition factor, the unassigned B-bit code points are not used. The adaptive allocation method can be advantageous when it is agreed that the repetition factor with the highest priority has the highest probability of occurrence based on the state-based method of the repetition request information, etc. Adaptive allocation can be difficult to apply when there is no priority among the repeating arguments to be sent, or when the priority among the repeating arguments is not known.

The base station and terminal can signal a repetition factor by performing at least some or all of the procedures described above.

Here, B, the number of bits for transmitting the repetition factor must be determined in advance. Also, the usage criteria and K at each stage may be determined in advance or may be determined through separate signaling. Basically, the purpose of the method through the present disclosure is to reduce signaling overhead, so it is preferable to determine the criteria and K in advance through such standard specifications, if possible.

Meanwhile, when determining K and the criterion to be used in each step through signaling in order to more dynamically transmit the repetition factor, the base station can transmit the relevant information to the terminal. The terminal can request or transmit the relevant information to the base station, but it is basically preferable that the determination of such criteria and parameters is performed in the base station or the network. When the base station notifies all terminals in the cell of K and the criterion to be used in each step in a terminal-specific manner, the base station can transmit information about K and the criterion to be used in each step through SIB1, SIB19, etc. When the base station notifies the terminal in a terminal-specific manner, the base station can transmit information about K and the criterion to be used in each step through the DAI field of DCI format 1_0 with CRC (cyclic redundancy check) scrambled by TC-RNTI of Msg4. Meanwhile, when the terminal requests the base station for information about K and the criterion to be used in each step, the base station can request information about K and the criterion to be used in each step through a separate PRACH occasion in Msg1 or a separate PRACH preamble in case of shared PRACH occasions or through Msg3. When applying this terminal request method, instead of accepting it as is, the base station can notify the criteria determined by considering the terminal's request through Msg4, etc.

FIGS. 21 to 24 are diagrams illustrating operations for determining and signaling a repetition factor according to the present disclosure.

Referring to Case 1 of Fig. 21, at step S2111, the base station can check the initial condition and perform the subsequent repeat factor signaling operation. Here, R _SIB can be {1, 2, 4, 8}.

In step S2112, the base station can select repetition factor candidates to be included in the signaling process. Here, the repetition factor candidates can be selected based on the state value of the repetition request information. Here, the number of repetition factors transmitted, K, can be 3, and the state of the repetition request information can be S _0. Therefore, among the repetition factors of R _SIB , K repetition factor candidates having small values are selected, and R ^* _SIB can be set to {1, 2, 4}.

In step S2113, the base station can set the priorities of the selected repetition factor candidates in the code point allocation process. Here, the priorities of the repetition factor candidates can be set based on the status value of the repetition request information. Accordingly, the priorities of the repetition factor candidates can be determined to have high priorities in the order of 1, 2, and 4.

In step S2114, the base station can assign the selected repetition factor candidates to code points. Here, the repetition factor candidates can be mapped to code points according to an adaptive preservation allocation method. And, the number of bits used to signal the repetition factor candidates can be 2. Accordingly, code point 0 can be assigned to repetition factor 1, code point 10 can be assigned to repetition factor 2, and code point 11 can be assigned to repetition factor 4.

Referring to Case 2 of Fig. 21, at step S2121, the base station may check the initial condition and perform the subsequent repeat factor signaling operation. Here, R _SIB may be {1, 2, 4, 8, 16, 32}. And, R _Msg3 may be 8.

In step S2122, the base station can select repetition factor candidates to be included in the signaling process. Here, the repetition factor candidates can be selected based on the state value of the repetition request information and the value of Msg3. Here, the number of repetition factors transmitted, K, can be 4, and the state of the repetition request information can be S _1. Therefore, among the repetition factors of R _SIB , K repetition factor candidates having values close to R _Msg3 are selected, and R ^* _SIB can be set to {4, 8, 16, 32}.

In step S2123, the base station can set the priorities of the selected repetition factor candidates in the code point allocation process. Here, the priorities of the repetition factor candidates can be set based on the selection order to R ^* _SIB . Accordingly, the priorities of the repetition factor candidates can be determined to have high priorities in the order of 8, 16, 4, and 32.

In step S2114, the base station can assign the selected repetition factor candidates to code points. Here, the repetition factor candidates can be mapped to code points according to an adaptive preservation allocation method. And, the number of bits used to signal the repetition factor candidates can be 3. Accordingly, code point 00 can be assigned to repetition factor 8, code point 10 can be assigned to repetition factor 16, code point 10 can be assigned to repetition factor 4, and code point 11 can be assigned to repetition factor 32. And, the last code point can be unused.

Referring to Case 1 of Fig. 22, at step S2211, the base station can check the initial condition and perform the subsequent repeat factor signaling operation. Here, R _SIB can be {1, 2, 4, 8}.

In step S2212, the base station can select repetition factor candidates to be included in the signaling process. Here, the repetition factor candidates can be selected based on the state value of the repetition request information. Here, the number of repetition factors transmitted, K, can be 2, and the state of the repetition request information can be S _1. Therefore, among the repetition factors of R _SIB , K repetition factor candidates having large values are selected, and R ^* _SIB can be set to {4, 8}.

Here, the step of setting the priority of the selected repeat argument candidates in the code point allocation process can be omitted.

In step S2213, the base station can assign the selected repetition factor candidates to code points. Here, the repetition factor candidates can be mapped to code points according to a preservation allocation method. And, the number of bits used to signal the repetition factor candidates can be 1. Accordingly, code point 0 can be assigned to repetition factor 4, and code point 1 can be assigned to repetition factor 8.

Referring to Case 2 of Fig. 22, at step S2221, the base station may check the initial condition and perform the subsequent repetition factor signaling operation. Here, R _SIB may be {1, 2, 4, 8, 16, 32}. And, R _Msg3 may be 8.

In step S2222, the base station can select repetition factor candidates to be included in the signaling process. Here, the repetition factor candidates can be selected based on the status value of the repetition request information and the value of Msg3. Here, the number of repetition factors transmitted, K, can be 4, and the status of the repetition request information can be S _0. Therefore, among the repetition factors of R _SIB , K repetition factor candidates having the smallest values are selected, and R ^* _SIB can be set to {1, 2, 4, 8}.

Here, the step of setting the priority of the selected repeat argument candidates in the code point allocation process can be omitted.

In step S2223, the base station can assign the selected repetition factor candidates to code points. Here, the repetition factor candidates can be mapped to code points according to an adaptive preservation allocation method. And, the number of bits used to signal the repetition factor candidates can be 3. Accordingly, code point 000 can be assigned to repetition factor 1, code point 001 can be assigned to repetition factor 2, code point 010 can be assigned to repetition factor 4, and code point 011 can be assigned to repetition factor 8. And, code points 100, 101, 110, and 111 may not be used.

Referring to case 1 of Fig. 23, the state of the repetition request information may be S ₁ .

At step S2311, the base station can check the initial conditions and perform subsequent iteration factor signaling operations, where R _SIB can be {2, 4, 8}.

Here, the number of repeated factors K transmitted can be 3. That is, R _SIB and R ^* _SIB can be identical to each other. Therefore, the step of selecting repeated factor candidates to be included in the signaling process can be omitted.

In step S2312, the base station can set the priorities of the selected repetition factor candidates in the code point allocation process. Here, the priorities of the repetition factor candidates can be set based on the status value of the repetition request information. Accordingly, the priorities of the repetition factor candidates can be determined to have high priorities in the order of 8, 4, and 2.

In step S2313, the base station can assign the selected repetition factor candidates to code points. Here, the repetition factor candidates can be mapped to code points according to an adaptive preservation allocation method. And, the number of bits used to signal the repetition factor candidates can be 2. Accordingly, code point 0 can be assigned to repetition factor 1, code point 10 can be assigned to repetition factor 2, and code point 11 can be assigned to repetition factor 4.

Referring to Case 2 of Fig. 23, at step S2321, the base station can check the initial condition and perform the subsequent repetition factor signaling operation. Here, R _SIB can be {1, 4, 8, 16}.

Here, the number of repeated factors K transmitted can be 4. That is, R _SIB and R ^* _SIB can be identical to each other. Therefore, the step of selecting repeated factor candidates to be included in the signaling process can be omitted.

In step S2322, the base station can set the priorities of the selected repetition factor candidates in the code point allocation process. Here, the priorities of the repetition factor candidates can be set based on the status value of the repetition request information. Accordingly, the priorities of the repetition factor candidates can be determined to have high priorities in the order of 1, 4, 8, and 16.

In step S2323, the base station can assign the selected repetition factor candidates to code points. Here, the repetition factor candidates can be mapped to code points according to an adaptive preservation allocation method. And, the number of bits used to signal the repetition factor candidates can be 3. Accordingly, code point 00 can be assigned to repetition factor 1, code point 10 can be assigned to repetition factor 4, code point 10 can be assigned to repetition factor 8, and code point 11 can be assigned to repetition factor 16. And, the last code point can be unused.

Referring to Case 1 of Fig. 24, at step S2411, the base station can check the initial condition and perform the subsequent repeat factor signaling operation. Here, R _SIB can be {1, 2, 4}.

Here, the number of repeated factors K transmitted can be 3. That is, R _SIB and R ^* _SIB can be identical to each other. Therefore, the step of selecting repeated factor candidates to be included in the signaling process can be omitted.

Additionally, the step of setting the priority of selected repeat argument candidates in the code point allocation process may be omitted.

In step S2412, the base station can assign the selected repetition factor candidates to code points. Here, the repetition factor candidates can be mapped to code points according to a fixed assignment method. And, the number of bits used to signal the repetition factor candidates can be 2. Accordingly, code point 00 can be assigned to repetition factor 1, code point 01 can be assigned to repetition factor 2, and code point 10 can be assigned to repetition factor 4. Code point 11 may not be used.

Referring to Case 2 of Fig. 24, at step S2421, the base station can check the initial condition and perform the subsequent repetition factor signaling operation. Here, R _SIB can be {1, 2, 4, 8, 16, 32}.

Here, the number of repeated factors K transmitted can be 6. That is, R _SIB and R ^* _SIB can be identical to each other. Therefore, the step of selecting repeated factor candidates to be included in the signaling process can be omitted.

Additionally, the step of setting the priority of selected repeat argument candidates in the code point allocation process may be omitted.

In step S2422, the base station can assign the selected repetition factor candidates to code points. Here, the repetition factor candidates can be mapped to the code points according to a preservation assignment method. And, the number of bits used to signal the repetition factor candidates can be 4. Accordingly, code point 000 can be assigned to repetition factor 1, code point 001 to repetition factor 2, code point 010 to repetition factor 4, code point 011 to repetition factor 8, code point 100 to repetition factor 16, and code point 101 to repetition factor 32. And, code points 110, 111, and the last bit may not be used.

FIG. 25 illustrates an example of a procedure for setting a repetition factor of an uplink control channel signal according to one embodiment of the present disclosure.

At step S2510, the base station can transmit to the terminal a message including information about candidates for a repetition factor indicating the number of times an uplink control channel is repeated.

At step S2520, the base station can receive a message including response information for setting up repeated transmission of an uplink control channel from the terminal.

At step S2530, the base station can determine a repetition factor of the uplink control channel according to preset criteria for determining a repetition factor of the uplink control channel based on the response information.

At step S2540, the base station can receive an uplink control channel signal from the terminal as many times as the repetition factor of the determined uplink control channel.

Here, the response information may include information for requesting repeated transmission of the uplink control channel.

Here, the response information may include information indicating whether the terminal supports repeated transmission of an uplink control channel, which is information distinct from information for requesting repeated transmission of an uplink control channel.

Here, the repetition factor of the uplink control channel can be determined based on statistical values of candidates for the repetition factor according to preset criteria.

Here, the repetition factor of the uplink control channel can be determined based on the number of times the response message is repeatedly transmitted, according to a preset criterion.

Here, the operating method may further include a step of signaling information indicating a repetition factor of an uplink control channel to the terminal.

Here, the step of signaling information indicating a repetition factor of an uplink control channel to a terminal may include the step of determining whether to signal information indicating a repetition factor of an uplink control channel based on candidates of repetition factors and response information, the step of mapping at least some of the candidates of repetition factors to code points based on whether to signal, and the step of signaling information indicating a repetition factor of the uplink control channel determined using the code points.

Here, the step of mapping at least some of the candidates of the repetition factor to the code point may be characterized by mapping a number of candidates of the repetition factor determined based on the number of bits of an information field indicating the repetition factor of the uplink control channel to the code point.

Here, the step of mapping at least some of the candidates for the repeating argument to code points may be characterized by mapping the candidates for the repeating argument to code points based on priorities of at least some of the candidates for the repeating argument.

The operation of the method according to the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. The computer-readable recording medium includes all types of recording devices that store information that can be read by a computer system. In addition, the computer-readable recording medium can be distributed over network-connected computer systems so that the computer-readable program or code can be stored and executed in a distributed manner.

Additionally, the computer-readable recording medium may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. The program instructions may include not only machine language codes produced by a compiler, but also high-level language codes that can be executed by the computer using an interpreter, etc.

While some aspects of the present disclosure have been described in the context of an apparatus, they may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a feature of a corresponding block or item or a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, at least one or more of the most significant method steps may be performed by such a device.

A programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described in the present disclosure. The field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described in the present disclosure. In general, the methods are preferably performed by some hardware device.

Although the present disclosure has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present disclosure without departing from the spirit and scope of the present disclosure as set forth in the claims below.

The present invention can be used in a device for transmitting and receiving a signal and a transmitter/receiver.

Claims (20)

In a method of operating a base station in a wireless communication system, A step of transmitting to a terminal a message including information about candidates for a repetition factor indicating the number of repetition transmissions of an uplink control channel; A step of receiving a message including response information for setting up repeated transmission of an uplink control channel from the terminal; A step of determining a repetition factor of an uplink control channel according to a preset criterion for determining a repetition factor of an uplink control channel based on the above response information; and A method comprising the step of receiving an uplink control channel signal from the terminal for a repetition factor of the determined uplink control channel. In claim 1, The above response information is, A method, characterized in that it includes information for requesting repeated transmission of the above uplink control channel. In claim 2, The above response information is, A method characterized in that it includes information indicating whether the terminal supports repeated transmission of the uplink control channel, which is information distinct from information for requesting repeated transmission of the uplink control channel. In claim 1, The repetition factor of the above uplink control channel is: A method characterized in that the determination is made based on statistical values of candidates for the repetition factor according to the above preset criteria. In claim 1, The repetition factor of the above uplink control channel is: A method characterized in that the number of times the response message is repeatedly transmitted is determined based on the above preset criteria. In claim 1, A method further comprising the step of signaling information indicating a repetition factor of the uplink control channel to the terminal. In claim 6, The step of signaling information indicating a repetition factor of the above uplink control channel to the terminal is as follows: A step of determining whether to signal information indicating a repetition factor of the uplink control channel based on candidates of the repetition factor and the response information; A step of mapping at least some of the candidates of the repetition factor to code points based on whether the signaling is performed; and A method comprising the step of signaling information indicating a repetition factor of the determined uplink control channel using the above code point. In claim 7, The step of mapping at least some of the candidates of the above repetition argument to code points is: A method characterized by mapping candidates of a number of repetition factors determined based on the number of bits of an information field indicating a repetition factor of the above uplink control channel to code points. In claim 7, The step of mapping at least some of the candidates of the above repetition argument to code points is: A method characterized in that the candidates of the repetition factor are mapped to code points based on priorities of at least some of the candidates of the repetition factor. In a method of operating a terminal in a wireless communication system, A step of receiving a message including information about candidates for a repetition factor indicating a repetition factor of an uplink control channel from a base station; A step of transmitting a message including response information for setting up repeated transmission of an uplink control channel to the base station; and A step of determining a repetition factor of an uplink control channel according to a preset criterion for determining a repetition factor of an uplink control channel based on the above response information; and A method comprising the step of transmitting an uplink control channel signal from the terminal a repetition factor of the determined uplink control channel. In claim 10, The above response information is, A method, characterized in that it includes information for requesting repeated transmission of the above uplink control channel. In claim 11, The above response information is, A method characterized in that it includes information indicating whether the terminal supports repeated transmission of the uplink control channel, which is information distinct from information for requesting repeated transmission of the uplink control channel. In claim 10, The repetition factor of the above uplink control channel is: A method characterized in that the determination is made based on statistical values of candidates for the repetition factor according to the above preset criteria. In claim 10, The repetition factor of the above uplink control channel is: A method characterized in that the number of times the response message is repeatedly transmitted is determined based on the above preset criteria. In claim 10, A method further comprising the step of receiving information indicating a repetition factor of the uplink control channel from the base station. In claim 15, Further comprising a step of mapping at least some of the candidates of the above repetition factor to code points, The repetition factor of the above uplink control channel is: A method characterized in that the method is set based on information indicating a repetition factor of the uplink control channel using the above code point. In claim 16, The step of mapping at least some of the candidates of the above repetition argument to code points is: A method characterized by mapping candidates of a number of repetition factors determined based on the number of bits of an information field indicating a repetition factor of the above uplink control channel to code points. In claim 16, The step of mapping at least some of the candidates of the above repetition argument to code points is: A method characterized in that the candidates of the repetition factor are mapped to code points based on priorities of at least some of the candidates of the repetition factor. In a base station operating in a wireless communication system, At least one transmitter; At least one receiver; at least one processor; and At least one memory operably connected to said at least one processor and storing instructions that, when executed, cause said at least one processor to perform a specific operation; The above specific actions are: Transmitting to a terminal a message including information about candidates for a repetition factor indicating the number of repetition transmissions of an uplink control channel; Receive a message including response information for setting up repeated transmission of an uplink control channel from the terminal; Determine the repetition factor of the uplink control channel according to a preset criterion for determining the repetition factor of the uplink control channel based on the above response information; and A base station that receives an uplink control channel signal from the terminal for a repetition factor of the determined uplink control channel. In a wireless communication system, at a terminal, At least one transmitter; At least one receiver; at least one processor; and At least one memory operably connected to said at least one processor and storing instructions that, when executed, cause said at least one processor to perform a specific operation; The above specific actions are: Receive a message including information about candidates for repetition factors indicating a repetition factor of an uplink control channel from a base station; Transmitting to the base station a message including response information for setting up repeated transmission of an uplink control channel; Determine the repetition factor of the uplink control channel according to a preset criterion for determining the repetition factor of the uplink control channel based on the above response information; and A terminal that transmits an uplink control channel signal from the terminal for a repetition factor of the determined uplink control channel.

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